Workpiece transfer device



June 23, 1964 H- M. SUOFY WORKPIECE TRANSFER DEVICE Filed Nov. 9, 1961 /Vz/Z Maida?? I modating various workpieces.

United States Patent() 3,138,128 WGRKPIECE TRANSFER DEVICE Hugh M. Suofy, Troy, Mich. (1100 Brooklawn, Birmingham, Mich.) Filed Nov. 9, 1961, Ser. No. 151,235 4 Claims. (Cl. 113-38) This invention relates generally to devices used to transfer workpieces from one station to another within a press or other machine and particularly relates to a device which is actuated automatically by the ram of a press to grip the workpieces and to move them progressively from one station to another so that a plurality of operations may be performed thereon in sequence.

The present invention is characterized by simplicity of construction which minimizes its setting up time on a press, and which minimizes its maintenance and mantlfacturing cost. The invention is further characterized in having a basic construction to which work grippers of a variety of shapes and sizes may be attached for accom- Moreover, this basic construction is such that the degree of motion thereof may readily be adjusted by the relatively simple substitution of cam segments of different conguration.

The main objects of the invention are to provide a workpiece transfer device of relatively simple and economical construction which is operable by the ram of a press to progressively transfer workpieces to various stations; to provide such a device with replaceable jaws for accommodating various shaped workpieces; to provide improved mechanical ca mming means for moving gripping jaws either to their gripping or released prositions prior to movement of a carriage which carries the gripping jaws; and to provide a workpiece transfer device with such simple construction that its degree of motion may be readily altered.

Further objects, advantages and novel features of the invention will become apparent from the following description in conjunction with the drawing wherein the single gure is an isometric view of the workpiece transfer device.

Referring to the drawing, the transfer device comprises a base 12 which may be provided with suitable bolt apertures or other attaching means for attaching the base to the bed of a press. The base may also be provided with suitable bolt apertures or other attaching means for supf porting a plurality of dies. The base thereby becomes a substitute press bed; however, for a permanent installation of the workpiece transfer device on a press, the base 12 may actually be the press bed. The device further comprises a pair of forward supports 15 and 16 and a pair of rear supports 18 and 20 which may be secured to the base 12 by bolts 22. These supports carry anti-friction bearings 24 and slidably receive the rods 26 and 2S of a carriage 30, which rods are secured to cross bar 32 by set screws 33 for simultaneous movement.

The cross bar is provided with a yoke portion 34 pivotally connected to a link 36 by a pin 3S. Link 36 is pivotally connected by a pin 40 to the yoke-shaped end of a bellerank 42 pivotally connected to a yoke 44 by a pin 46. Yoke 44 is secured to the base 12 by suitable means such as Allen bolts 47. The other yoke-shaped end of the bellcrank is pivotally connected by a pin 48 to the end of an actuating bar 50 which carries a lower stop member 52 and an upper stop member 54. Set screws 56 adjustably secure these stop members to the bar 50. The lower stop member 52 threadably receives a threaded stud 60 shown by dotted lines which may be adjusted up or down with respect to the bottom 61 of an actuating arm 62 which is connected to the ram of a press and slidably receives the bar 50 in a bearing formed by the yoke 63 and pin 64. The upper stop member 54 is provided with a threaded 3,138,128 Patented June 23, 1964 ICC stud 66 which may also be adjusted up or down with respect to the arm 62.

It is seen that as the arm 62 is moved up into engagement with the stud 66, the bellcrank 42 will be rotated in a clockwise direction to move the carriage 30 to the right. As the ram is then urged downwardly on its work stroke, the arm 62 will engage the lower stop 60 and rotate the bellcrank 42 to the position shown in the drawing. It is seen from the figure that portion 69 of bar 50 is spaced above the bellcrank and the link member 36 to allow the bellcrank to rotate its full amount in the counterclockwise direction.

A pair of work gripping jaws 68 and 70 are supported by suitable pin or other attaching means 72 to a pair of slides generally designated 74 and 76 respectively. Slide 74 comprises a pair of rods 78 and S0 slidably mounted in anti-friction bearings 82 secured in block members 86 and 8S locked onto the rod 26 by suitable set screw means 90. lt is noted that bearings 24 and 82 are preferably of the ball type so as to provide very little frictional resistance to the motions of carriage 30 and slides 74 and 76. A connecting rod 92 is provided with socket members 94 and 96 which are locked onto the ends of rods 78 and 80 respectively by set screws 98.

Rod 92 forms a cam follower which is slidable within a slot 100 formed in a cam member 102 which is adapted for connection to a press ram by connecting plate 103. An intermediate portion 104 of the slot 100 is angularly directed to provide a cam surface 106 for urging the slide 74 inwardly to the left on the upstroke of the press ram and to provide a cam surface 103 for urging the slide '.74 outwardly to the right on thedownstroke of the press ram. Slide 76 is of identical construction to slide 74 but is reversed in its operation so that the jaws 68 and 70 are moved together in a work-gripping relationship by the upward motion of the press ram. A cam member 114 for moving the slide '76 is identical to cam member 102 but is reversed in position. The various parts of slide '76 and member 114 which correspond in shape and function to the parts of slide 74 and member 102 are similarly numbered.

In the operation of the transfer device, suitable workpiece dispensing means of any well known construction depending on the workpiece shape may be provided for automatically dispensing the workpieces one at a time to a position on the iirst die face aligned with the gripping portions 116 and 118 of the jaws. The dispensing action may take place during the upward travel of the press ram. Continued intermediate upward motion of the ram causes the cam surfaces 106 of the cam members 102 and 114 to engage the cam followers 92 to move the jaws together to clamp or surround the workpieces which are aligned with the pairs of gripping portions 116-118, 120-122,

124-126 and so on. Continued final upward motion of the ram causes the cam followers 92 to slide within the lower dwell portions 128 of the cam members while simultaneously causing the actuating arm 62 to engage the upper stop 66 on the actuating bar 50 to cause the bellcrank 42 to be rotated in a clockwise direction to move the carriage 30 to its forward position. The new workpiece which is carried by the portions 116 and 118 of the jaws will be moved into the rst die while the prior workpieces will be progressively moved into the second, third, and fourth dies and so on. Suitable means may be provided at the forward end of the transfer device for receiving and carrying away workpieces which are moved from the last die, and this operation conveniently takes place as the rods 92 traverse the lower vertical portions of the slots 12S and the arm 62 moves without eiect away from the upper stop 54. Continued intermediate down- Ward motion of the press ram causes the cam surfaces 108 of the cam members to engage the cam followers to move the slides and the work jaws to their outward positions as shown in the figure. Final downward motion of the press ram will move the cam followers into the upper dwell portions 130 of the slots 100 while simultaneously engaging the arm 62 witht he lower stop 60 to rotate the beilcrank in a counterclockwise direction and move the carriage to its retracted position. Retraction of the press ram will again actuate the workpiece dispensing mechanism to place another workpiece in alignment with portions H6 and 118 of the jaws and the progressive movement cycle is repeated. The work-gripping portions 116, 11S, 120, 122, 124 and 126 may be of any suitable configuration for gripping the workpieces. For example, if the press operations gradually increase the diameters of the workpieces each progressively situated pair of said gripping portions are made slightly larger than the preceding pair. A shoulder 132 on bellcrank 42 engages the top 134 of yoke 44 to limit its clockwise motion, and shoulder 136 engages the lower edge 138 of the yoke to limit its counterclockwise motion.

Where dies are employed which require the workpiece to be formed thereinto, suitable lifting means must be provided in the die to move the workpieces out of the die cavities to the level of the die faces so that the gripping jaws will be able to carry or slide the workpieces across the face portions of the several dies intermediate the die cavities. It is noted that the spacing of the stops 60 and 66 is such that the workpieces are either gripped or completely released by the jaws prior to the engagement of the arm 62 with these stops.

While it will be apparent that the embodiment of the invention herein disclosed is well calculated to fulfill the objects of the invention, it will be appreciated that the invention is susceptible to modification, variation and change without departing from the proper scope or fair meaning of the subjoined claims.

What is claimed is:

1. A work transfer device for use in conjunction with a press of the type having a reciprocable part, said device comprising stationary support means, a carriage reciprocably mounted on said support means for movement between forward and rearward positions, jaw means reciprocably mounted on said carriage and movable between work gripping and work release positions, cam follower means on said jaw means, cam means adapted for attachment to said part and having terminal dwell portions and an intermediate actuator portion, the latter being engageable with said cam follower means for moving said jaw means to its gripping position during an intermediate portion of the upstroke of said part and to its release position during an intermediate portion of the downstroke of said part, lever means on said support means and attached by a lost motion connection to said carriage, said lever means also being being engageable with said part for actuation thereby to move said carriage to its forward position during the terminal portion of the upstroke of said part and to its rearward position during the terminal portion of the downstroke of said part.

2. A work transfer device for use in conjunction with a press of the type having a vertically reciprocal ram, comprising support means, a carriage reciprocably mounted on said support means for movement between forward and rearward positions, jaw means reciprocably mounted on said carriage and movable between work gripping and work release positions, cam follower means on said jaw means, cam means adapted for attachment to said ram and having terminal dwell portions and an intermediate actuator portion, the latter being engageable with said cam follower means for moving said jaw means to its gripping position during an intermediate portion of the ram upstroke and to its release position during an intermediate portion of the ram downstroke, lever means on said support means and attached by a lost motion connection to said carriage, said lever means being engageable by said ram for actuation thereby to move said carriage to its forward positon during the terminal portion of the upstroke of said ram and to its rearward position during the terminal portion of the downstroke of said ram, said cam means being engageable with said cam follower means prior to the actuation of said lever means.

3. A work transfer device for use in conjunction with a press, comprising a base, a carriage reciprocably mounted on said base for movement between forward and rearward positions, a pair of jaws mounted on a pair of slides reciprocably mounted on opposite sides of said carriage and slidable thereon to move said jaws between work gripping and work release positions, said slides each comprising a pair of shafts and a connecting rod, said rods forming cam followers, a pair of cam means adapted for attachment to a reciprocable portion of the press and having terminal portions and an intermediate actuator portion, the latter being engageable with one each of said cam followers for moving said slides and jaws to their gripping positions during an intermediate portion of the press ram upstroke and to their release positions during an intermediate portion of the press ram downstroke, lever means on said base and connected to said carriage, said lever means being engageable with a reciprocable portion of the press for actuation thereby to move said carriage to its forward position during the terminal portion of the upstroke of the press ram and to its rearward position on the downstroke of the press ram, said cam means being engageable with said cam followers prior to the actuation of said lever means.

4. A work transfer device for use in conjunction with a press, comprising a base, a carriage reciprocably mounted on said base for movement between forward and rearward positions, a pair of jaws mounted on a pair of slides reciprocably mounted on opposite sides of said carriage and slidable thereon to move said jaws between work gripping and work release positions, said slides each comprising a pair of shafts and a connecting rod, said rods forming cam followers, a pair of cam means adapted for attachment to a reciprocable portion of the press and having terminal dwell portions and an intermediate actuator portion, the latter being engageable with one each of said cam followers for moving said slides and jaws to their gripping positions during an intermediate portion of the press ram upstroke and to their release positions on the press ram downstroke, each of said cam means comprising a bar having a slot therein slidably receiving one each of said connecting rods, lever means on said base and connected to said carriage, said lever means being engageable with a reciprocable portion of the press for actuation thereby to move said carriage to its forward position during the terminal portion of the upstroke of the press ram and to its rearward position during the terminal portion of the downstroke of the press ram, said cam means being engageable with said cam followers prior to the actuation of said lever means.

References Cited in the tile of this patent UNITED STATES PATENTS 649,071 Paull et al. May 8, 1900 2,640,401 Comstock June 2, 1953 3,057,312 Hatch Oct. 9, 1962 FOREIGN PATENTS 808,011 Great Britain Jan. 28, 1959 847,329 Great Britain Sept. 7, 1960 

1. A WORK TRANSFER DEVICE FOR USE IN CONJUNCTION WITH A PRESS OF THE TYPE HAVING A RECIPROCABLE PART, SAID DEVICE COMPRISING STATIONARY SUPPORT MEANS, A CARRIAGE RECIPROCABLY MOUNTED ON SAID SUPPORT MEANS FOR MOVEMENT BETWEEN FORWARD AND REARWARD POSITIONS, JAW MEANS RECIPROCABLY MOUNTED ON SAID CARRIAGE AND MOVABLE BETWEEN WORK GRIPPING AND WORK RELEASE POSITIONS, CAM FOLLOWER MEANS ON SAID JAW MEANS, CAM MEANS ADAPTED FOR ATTACHMENT TO SAID PART AND HAVING TERMINAL DWELL PORTIONS AND AN INTERMEDIATE ACTUATOR PORTION, THE LATTER BEING ENGAGEABLE WITH SAID CAM FOLLOWER MEANS FOR MOVING SAID JAW MEANS TO ITS GRIPPING POSITION DURING AN INTERMEDIATE PORTION OF THE UPSTROKE OF SAID PART AND TO ITS RELEASE POSITION DURING AN INTERMEDIATE PORTION OF THE DOWNSTROKE OF SAID PART, LEVER MEANS ON SAID SUPPORT MEANS AND ATTACHED BY A LOST MOTION CONNECTION TO SAID CARRIAGE, SAID LEVER MEANS ALSO BEING BEING ENGAGEABLE WITH SAID PART FOR ACTUATION THEREBY TO MOVE SAID CARRIAGE TO ITS FORWARD POSITION DURING THE 